74% (2002)

60% (2004)

70% (1992)

72% (1994)

77% (1999)

61% (1999)

71% (1988)

71% (1979)

61% (1974)

76% (1986)

70% (2002)

68% (1974)

77% (1986)

67% (1989)

61% (1995)

63% (1983)

78% (1969)

68% (1993)

60% (1972)

61% (1981)